Enhanced acknowledgment and power saving for wireless communications

ABSTRACT

This disclosure describes systems, methods, and devices related to using enhanced acknowledgment and power save. A device may determine a multi-user (MU) multiple-input multiple-output (MIMO) frame associated with a MU-MIMO group. The device may determine a first portion of the MU-MIMO frame associated with the first station device of the MU-MIMO group, wherein the first portion comprises a first indication of a first time offset associated with the first station device. The device may determine a second portion of the MU-MIMO frame associated with the second station device of the MU-MIMO group, wherein the second portion comprises a second indication of a second time offset associated with the second station device. The device may cause to send the MU-MIMO frame to the MU-MIMO group. The device may identify a first acknowledgment from the first station device based on the first time offset.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.16/169,917, filed Oct. 24, 2018, which claims the benefit of U.S.Provisional Application No. 62/576,468, filed Oct. 24, 2017, and U.S.Provisional Application No. 62/581,515, filed Nov. 3, 2017, thedisclosures of which are incorporated herein by reference as if setforth in full.

TECHNICAL FIELD

This disclosure generally relates to systems and methods for wirelesscommunications and, more particularly, to enhanced acknowledgment andpower saving for wireless communications.

BACKGROUND

Wireless devices are becoming widely prevalent and are increasinglyrequesting access to wireless channels. Wireless devices may improveperformance through efficient transmissions and controls.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts a network diagram illustrating an example networkenvironment, according to some example embodiments of the presentdisclosure.

FIG. 1B depicts a network diagram illustrating an example networkenvironment, according to some example embodiments of the presentdisclosure.

FIG. 2 illustrates an acknowledgment and power save sequence, accordingto some example embodiments of the present disclosure.

FIG. 3 illustrates an acknowledgment and power save sequence, inaccordance with one or more example embodiments of the presentdisclosure.

FIGS. 4A-4D illustrate throughput of an acknowledgment and power savesequence, in accordance with one or more example embodiments of thepresent disclosure.

FIG. 5 illustrates a multi-user data sequence, in accordance with one ormore example embodiments of the present disclosure.

FIGS. 6A-6B illustrate throughput of a multi-user data sequence, inaccordance with one or more example embodiments of the presentdisclosure.

FIG. 7A depicts a flow diagram of an illustrative process for usingenhanced acknowledgment and power save, in accordance with one or moreexample embodiments of the present disclosure.

FIG. 7B depicts a flow diagram of an illustrative process for usingenhanced acknowledgment and power save, in accordance with one or moreexample embodiments of the present disclosure.

FIG. 8 illustrates a functional diagram of an example communicationstation that may be suitable for use as a user device, in accordancewith one or more example embodiments of the present disclosure.

FIG. 9 is a block diagram of an example machine upon which any of one ormore techniques (e.g., methods) may be performed, in accordance with oneor more example embodiments of the present disclosure.

DETAILED DESCRIPTION

The following description and the drawings sufficiently illustratespecific embodiments to enable those skilled in the art to practicethem. Other embodiments may incorporate structural, logical, electrical,process, and other changes. Portions and features of some embodimentsmay be included in or substituted for, those of other embodiments.Embodiments set forth in the claims encompass all available equivalentsof those claims.

The IEEE 802.11ad standard, also known as WiGig, is evolving into a newIEEE 802.11ay standard in a millimeter wave (mmWave) band (e.g., 60GHz). A physical (PHY) layer of IEEE 802.1 lay may suggest amulti-gigabit throughput achieved using large bandwidth and multi-usermultiple input, multiple output (MU-MIMO). Theoretically, MU-MIMO usingeight streams may increase an access point (AP) throughput eight times,but AP throughput may be reduced by large medium access control (MAC)overhead caused by an existing acknowledgment flow. This acknowledgmentoverhead may achieve 95% of a duration of one MU cycle (e.g., an MUframe transmission and acknowledgment). Another significant problem inthe evolution to IEEE 802.11ay may be power consumption. An effectivepower save solution, therefore, may be implemented for an MU-MIMOtransmission flow.

Existing solutions may consider a transmission of an MU frame to severalstations (STAs), and then polling each of the STAs sequentially foracknowledgment. Alternatively, a block association request/blockassociation (BAR/BA) order may be the same as association identifiers(AIDs), which may appear in a group description present in an enhanceddigital multi-gigabit (EDMG) Group ID Set element corresponding to an MUgroup. The ordered BAR/BA exchange sequence may enable each STA to knowwhen the STA should wake up to receive the corresponding BAR frameaddressed to the STA. This may allow STAs to be in a power save mode forup to 86% of a duration of an MU-MIMO transmission and acknowledgmentperiod.

Existing MU-MIMO acknowledgment and power save flows may have thefollowing issues. A BAR/BA exchange may cause large overhead increasingthe duration of one MU cycle, and therefore may significantly reducethroughput. The overhead may achieve 95% of a duration of one MU cycle.A power save approach may limit an MU-MIMO acknowledgment flow to onlyone case: when all STAs are requested for BA after each MU PPDU. Thisapproach may not allow the use of a flow in which an AP requests a BAfrom only one STA after each MU PPDU, thereby reducing theacknowledgment overhead. In addition, an MU-MIMO power save may be basedon an assumption that all STAs transmit the smallest BA, which may notbe accurate when BAs of bigger size are used. These issues may beaddressed by the example embodiments described herein.

IEEE 802.11ay task group started development of the new standard in themmWave (60 GHz) band which is an evolution of the IEEE 802.11ad standardalso known as WiGig. IEEE 802.11ay proposes to increase the transmissiondata rate by applying Multiple Input Multiple Output (MIMO) and channelbonding techniques.

802.11ay makes use of the unlicensed 60 GHz mmWave frequency band. Thewideband frequency and its directivity nature make it attractive forservice providers who want to deliver high-speed internet to residentialhouses. This kind of network is built with many nodes communicating witheach other creating a distributed mesh network. One of the methods toallocate link access in those controlled networks is by dividing themedium between uplink and downlink slots and further dividing each ofthe slots into several TDD-SPs (time division duplex service period).The TDD-SPs are allocated to different stations allowing the controlledlink access to be managed by a central server and operator. In each ofthe TDD-SPs, the station may transmit or receive but not both. Thismethod of allocating the medium helps mitigate interferences amongstations. This method is also known by the name TDD (Time DivisionDuplex). In order to manage the network per traffic usage, service levelagreement, network load, etc., the central controller needs to send andreceive management messages that collect the bandwidth request from thestations and allocate the bandwidth of the network. Bandwidth allocationis done by assigning uplink and downlink TDD-SPs to specific users.

One of the most significant features of the new standard is support ofMU-MIMO. To increase its efficiency and to reduce the overhead caused bylong acknowledgment procedure the MU-MIMO acknowledgment flow considersthat STAs transmit their acknowledgments in scheduled periods.

On the other hand, IEEE 802.1 lay proposes several new use cases to besupported in the future standard and one of them is “mmWave DistributionNetworks” which considers that all transmissions in the networkincluding the acknowledgments are slotted. Both of the mentioned casesrequire new Ack policy, which will indicate the transmission ofacknowledgments in the scheduled slots.

Now, 802.11ad stations support three types of Ack policy indication (twobits available):

00—Implicit Block Ack Request. The addressed recipient returns aBlockAck frame SIFS after the physical layer convergence protocol (PLCP)data unit (PPDU) carrying the QoS Data frames.

10—No Ack. The recipient will not transmit the acknowledgment inresponse to the frame.

11—Block Ack. The addressed recipient takes no action upon the receiptof the frame except for recording the state. The recipient returnsBlockAck frame short inter-frame space (SIFS) after BlockAckReq frame orimplicit block ack request in the future.

The existing solutions do not consider the acknowledgment procedure in ascheduled timeslot. The usage of the existing Ack policy indications inthe cases with scheduled acknowledgment may confuse EDMG STAs.

Example embodiments described herein provide certain systems, methods,and devices for enhanced acknowledgment and power save for the IEEE802.11 family of standards, including the IEEE 802.11ay standard.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate a new procedure for MU-MIMO acknowledgment andpower save. The enhanced acknowledgment and power saving may facilitatethe removal of BAR frames and BA transmission according to a defined(e.g., explicitly or implicitly) schedule. Power save may also followthe schedule.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate that BAR frames may be removed from anacknowledgment flow in order to reduce overhead. STAs may transmit theirBA during time slots scheduled by a personal basic service set controlpoint (PCP) AP (PCP/AP) for each STA.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate that a PCP/AP (e.g., PCP/AP 302) may schedule timeslots for a BA transmission for each STA considering knowledge about theBA type for each STA and that BAs may be transmitted with the lowestmodulation and coding scheme (MCS). A PCP/AP may inform each STA of theSTA's respective BA Transmission Time (BATT) by including schedulinginformation into the same MU PPDU.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate additional information in the MU-PPDU to indicateto the STAs timing associated with a next MU-PPDU that may be sent bythe PCP/AP.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate each STA may implement a power save mode afterreceiving an MU PPDU (e.g., an “end of frame” detection may be used forearlier receiver stop). The STA may wake up for BA transmission, and mayreturn to a power save mode again until the time defined by AP (e.g.,until the next MU PPDU transmission). The STA may follow the schedulinginformation and may wake up exactly for the STA's BA transmission and MUPPDU reception, thereby performing power save in an effective andaccurate way.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate that scheduling information delivered from aPCP/AP to an STA may be specific to an STA, and may include a BATT Startoffset, which may indicate a beginning of time slot provided by thePCP/AP for an STA to transmit the STA's BA.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may facilitate scheduling information delivered from a PCP/AP toan STA may be specific to an STA, and may include a next PPDU Startoffset, which may indicate the moment when an STA should begin listeningto/for the PCP/AP. At this moment, the PCP/AP may either starttransmitting the next MU PPDU in a current sequence of an MU-MIMOtransmission or may transmit a BAR to an STA if a solicited BA was notreceived.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may significantly reduce acknowledgment overhead, providingoutstanding throughput gains (e.g., up to 750%) compared to legacyprocedures.

In one or more embodiments, an enhanced acknowledgment and power savingsystem may allow an STA to perform a power save in a most effective andaccurate way that may yield a 76% reduction of STA awake time comparedto legacy procedures.

A directional multi-gigabyte (DMG) communications may involve one ormore directional links to communicate at a rate of multiple gigabits persecond, for example, at least 1 gigabit per second, 7 gigabits persecond, or any other rate. An amendment to a DMG operation in a 60 GHzband, e.g., according to an IEEE 802.11ad standard, may be defined, forexample, by an IEEE 802.11ay project.

In some demonstrative embodiments, one or more devices may be configuredto communicate over a next generation 60 GHz (NG60) network, an enhancedDMG (EDMG) network, and/or any other network. For example, the one ormore devices may be configured to communicate over the NG60 or EDMGnetworks.

In one embodiment, an enhanced acknowledgment policy system may define anew Ack policy indication for scheduled acknowledgment in IEEE 802.11ay.The enhanced acknowledgment policy system may make the Ack policycomprehensible for EDMG stations.

The above descriptions are for purposes of illustration and are notmeant to be limiting. Numerous other examples, configurations,processes, etc., may exist, some of which are described in greaterdetail below. Example embodiments will now be described with referenceto the accompanying figures.

FIG. 1A depicts a network diagram illustrating an example networkenvironment, according to some example embodiments of the presentdisclosure. Wireless network 100 may include one or more user devices120 and one or more responding device(s) (e.g., AP 102), which maycommunicate in accordance with IEEE 802.11 communication standards. Theuser device(s) 120 may be mobile devices that are non-stationary (e.g.,not having fixed locations) or may be stationary devices.

In some embodiments, the user devices 120 and the AP 102 may include oneor more computer systems similar to that of the functional diagram ofFIG. 8 and/or the example machine/system of FIG. 9.

One or more illustrative user device(s) 120 and/or AP(s) 102 may beoperable by one or more user(s) 110. It should be noted that anyaddressable unit may be a station (STA). An STA may take on multipledistinct characteristics, each of which shapes its function. Forexample, a single addressable unit might simultaneously be a portableSTA, a quality-of-service (QoS) STA, a dependent STA, and a hidden STA.The one or more illustrative user device(s) 120 and the AP(s) 102 may beSTAs. The one or more illustrative user device(s) 120 and/or AP(s) 102may operate as a personal basic service set (PBSS) control point/accesspoint (PCP/AP). The user device(s) 120 (e.g., 124, 126, or 128) and/orAP(s) 102 may include any suitable processor-driven device including,but not limited to, a mobile device or a non-mobile, e.g., a static,device. For example, user device(s) 120 and/or AP(s) 102 may include, auser equipment (UE), a station (STA), an access point (AP), a softwareenabled AP (SoftAP), a personal computer (PC), a wearable wirelessdevice (e.g., bracelet, watch, glasses, ring, etc.), a desktop computer,a mobile computer, a laptop computer, an ultrabook computer, a notebookcomputer, a tablet computer, a server computer, a handheld computer, ahandheld device, an internet of things (IoT) device, a sensor device, aPDA device, a handheld PDA device, an on-board device, an off-boarddevice, a hybrid device (e.g., combining cellular phone functionalitieswith PDA device functionalities), a consumer device, a vehicular device,a non-vehicular device, a mobile or portable device, a non-mobile ornon-portable device, a mobile phone, a cellular telephone, a PCS device,a PDA device which incorporates a wireless communication device, amobile or portable GPS device, a DVB device, a relatively smallcomputing device, a non-desktop computer, a “carry small live large”(CSLL) device, an ultra mobile device (UMD), an ultra mobile PC (UMPC),a mobile internet device (MID), an “origami” device or computing device,a device that supports dynamically composable computing (DCC), acontext-aware device, a video device, an audio device, an A/V device, aset-top-box (STB), a blu-ray disc (BD) player, a BD recorder, a digitalvideo disc (DVD) player, a high definition (HD) DVD player, a DVDrecorder, a HD DVD recorder, a personal video recorder (PVR), abroadcast HD receiver, a video source, an audio source, a video sink, anaudio sink, a stereo tuner, a broadcast radio receiver, a flat paneldisplay, a personal media player (PMP), a digital video camera (DVC), adigital audio player, a speaker, an audio receiver, an audio amplifier,a gaming device, a data source, a data sink, a digital still camera(DSC), a media player, a smartphone, a television, a music player, orthe like. Other devices, including smart devices such as lamps, climatecontrol, car components, household components, appliances, etc. may alsobe included in this list.

As used herein, the term “Internet of Things (IoT) device” is used torefer to any object (e.g., an appliance, a sensor, etc.) that has anaddressable interface (e.g., an Internet protocol (IP) address, aBluetooth identifier (ID), a near-field communication (NFC) ID, etc.)and can transmit information to one or more other devices over a wiredor wireless connection. An IoT device may have a passive communicationinterface, such as a quick response (QR) code, a radio-frequencyidentification (RFID) tag, an NFC tag, or the like, or an activecommunication interface, such as a modem, a transceiver, atransmitter-receiver, or the like. An IoT device can have a particularset of attributes (e.g., a device state or status, such as whether theIoT device is on or off, open or closed, idle or active, available fortask execution or busy, and so on, a cooling or heating function, anenvironmental monitoring or recording function, a light-emittingfunction, a sound-emitting function, etc.) that can be embedded inand/or controlled/monitored by a central processing unit (CPU),microprocessor, ASIC, or the like, and configured for connection to anIoT network such as a local ad-hoc network or the Internet. For example,IoT devices may include, but are not limited to, refrigerators,toasters, ovens, microwaves, freezers, dishwashers, dishes, hand tools,clothes washers, clothes dryers, furnaces, air conditioners,thermostats, televisions, light fixtures, vacuum cleaners, sprinklers,electricity meters, gas meters, etc., so long as the devices areequipped with an addressable communications interface for communicatingwith the IoT network. IoT devices may also include cell phones, desktopcomputers, laptop computers, tablet computers, personal digitalassistants (PDAs), etc. Accordingly, the IoT network may be comprised ofa combination of “legacy” Internet-accessible devices (e.g., laptop ordesktop computers, cell phones, etc.) in addition to devices that do nottypically have Internet-connectivity (e.g., dishwashers, etc.).

The user device(s) 120 and/or AP(s) 102 may also include mesh stationsin, for example, a mesh network, in accordance with one or more IEEE802.11 standards and/or 3GPP standards.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to communicate with each other via one ormore communications networks 130 and/or 135 wirelessly or wired. Theuser device(s) 120 may also communicate peer-to-peer or directly witheach other with or without the AP(s) 102. Any of the communicationsnetworks 130 and/or 135 may include, but not limited to, any one of acombination of different types of suitable communications networks suchas, for example, broadcasting networks, cable networks, public networks(e.g., the Internet), private networks, wireless networks, cellularnetworks, or any other suitable private and/or public networks. Further,any of the communications networks 130 and/or 135 may have any suitablecommunication range associated therewith and may include, for example,global networks (e.g., the Internet), metropolitan area networks (MANs),wide area networks (WANs), local area networks (LANs), or personal areanetworks (PANs). In addition, any of the communications networks 130and/or 135 may include any type of medium over which network traffic maybe carried including, but not limited to, coaxial cable, twisted-pairwire, optical fiber, a hybrid fiber coaxial (HFC) medium, microwaveterrestrial transceivers, radio frequency communication mediums, whitespace communication mediums, ultra-high frequency communication mediums,satellite communication mediums, or any combination thereof.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128) andAP(s) 102 may include one or more communications antennas. The one ormore communications antennas may be any suitable type of antennascorresponding to the communications protocols used by the user device(s)120 (e.g., user devices 124, 126 and 128), and AP(s) 102. Somenon-limiting examples of suitable communications antennas include Wi-Fiantennas, Institute of Electrical and Electronics Engineers (IEEE)802.11 family of standards compatible antennas, directional antennas,non-directional antennas, dipole antennas, folded dipole antennas, patchantennas, multiple-input multiple-output (MIMO) antennas,omnidirectional antennas, quasi-omnidirectional antennas, or the like.The one or more communications antennas may be communicatively coupledto a radio component to transmit and/or receive signals, such ascommunications signals to and/or from the user devices 120 and/or AP(s)102.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to perform directional transmission and/ordirectional reception in conjunction with wirelessly communicating in awireless network. Any of the user device(s) 120 (e.g., user devices 124,126, 128), and AP(s) 102 may be configured to perform such directionaltransmission and/or reception using a set of multiple antenna arrays(e.g., directional multi-gigabit (DMG) antenna arrays or the like). Eachof the multiple antenna arrays may be used for transmission and/orreception in a particular respective direction or range of directions.Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to perform any given directionaltransmission towards one or more defined transmit sectors. Any of theuser device(s) 120 (e.g., user devices 124, 126, 128), and AP(s) 102 maybe configured to perform any given directional reception from one ormore defined receive sectors.

Multiple Input, Multiple Output (MIMO) beamforming in a wireless networkmay be accomplished using RF beamforming and/or digital beamforming. Insome embodiments, in performing a given MIMO transmission, user devices120 and/or AP(s) 102 may be configured to use all or a subset of its oneor more communications antennas to perform MIMO beamforming.

Any of the user devices 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may include any suitable radio and/or transceiver fortransmitting and/or receiving radio frequency (RF) signals in thebandwidth and/or channels corresponding to the communications protocolsutilized by any of the user device(s) 120 and AP(s) 102 to communicatewith each other. The radio components may include hardware and/orsoftware to modulate and/or demodulate communications signals accordingto pre-established transmission protocols. The radio components mayfurther have hardware and/or software instructions to communicate viaone or more Wi-Fi and/or Wi-Fi direct protocols, as standardized by theInstitute of Electrical and Electronics Engineers (IEEE) 802.11standards. In certain example embodiments, the radio component, incooperation with the communications antennas, may be configured tocommunicate via 2.4 GHz channels (e.g., 802.11b, 802.11g, 802.11n,802.11ax), 5 GHz channels (e.g., 802.11n, 802.11ac, 802.11ax), or 60 GHzchannels (e.g., 802.11ad, 802.11ay). In some embodiments, non-Wi-Fiprotocols may be used for communications between devices, such asBluetooth, dedicated short-range communication (DSRC), Ultra-HighFrequency (UHF) (e.g., IEEE 802.11af, IEEE 802.22), white band frequency(e.g., white spaces), or other packetized radio communications. Theradio component may include any known receiver and baseband suitable forcommunicating via the communications protocols. The radio component mayfurther include a low noise amplifier (LNA), additional signalamplifiers, an analog-to-digital (A/D) converter, one or more buffers,and digital baseband.

When an AP (e.g., AP 102) establishes communication with one or moreuser devices 120 (e.g., user devices 124, 126, and/or 128), the AP 102may communicate in a downlink direction and the user devices 120 maycommunicate with the AP 102 in an uplink direction by sending frames ineither direction. The user devices 120 may also communicate peer-to-peeror directly with each other with or without the AP 102. The frames maybe preceded by one or more preambles that may be part of one or moreheaders. These preambles may be used to allow a device (e.g., AP 102and/or user devices 120) to detect a new incoming data frame fromanother device. A preamble may be a signal used in networkcommunications to synchronize transmission timing between two or moredevices (e.g., between the APs and user devices).

The IEEE 802.11 standard defines various frame types that devices mayuse for communications as well as managing and controlling the wirelesslink. These frame types may include data frames or signaling frames. Thesignaling frames may be divided into control frames and managementframes. Management frames enable devices to establish and maintaincommunications. Some examples of management frames may include, but arenot limited to, fine timing measurement frame, authentication frames,association request frame, association response frame, beacon frame,etc. Control frames may assist in the delivery of data frames betweendevices. Some examples of control frames may include, but are notlimited to, request to send frame, clear to send frame, acknowledgmentframe, etc.

Typically, control frames have limited and simpler structures thanmanagement frames. Meaning that baseband processing may process controlframes using a simpler procedure, resulting in faster processing.However, control frames are less flexible than management frames.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), and AP102 may be configured to communicate with each other via one or morecommunications networks 130 and/or 135 wirelessly or wired. Any of thecommunications networks 130 and/or 135 may include, but are not limitedto, any one of a combination of different types of suitablecommunications networks such as, for example, broadcasting networks,cable networks, public networks (e.g., the Internet), private networks,wireless networks, cellular networks, or any other suitable privateand/or public networks. Further, any of the communications networks 130and/or 135 may have any suitable communication range associatedtherewith and may include, for example, global networks (e.g., theInternet), metropolitan area networks (MANs), wide area networks (WANs),local area networks (LANs), or personal area networks (PANs). Inaddition, any of the communications networks 130 and/or 135 may includeany type of medium over which network traffic may be carried including,but not limited to, coaxial cable, twisted-pair wire, optical fiber, ahybrid fiber coaxial (HFC) medium, microwave terrestrial transceivers,radio frequency communication mediums, white space communicationmediums, ultra-high frequency communication mediums, satellitecommunication mediums, or any combination thereof.

In one embodiment, and with reference to FIG. 1A, when an AP (e.g.,AP(s) 102) establishes communication with one or more user devices 120(e.g., user devices 124, 126, and/or 128), the AP 102 may communicate ina downlink direction and the user devices 120 may communicate with theAP 102 in an uplink direction by sending frames in either direction.

In one or more embodiments, the AP 102 and the one or more user devices120 may implement an enhanced acknowledgment and power saving duringMU-MIMO communications.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 1B depicts an illustrative schematic diagram 150 for an enhancedacknowledgment policy system, in accordance with one or more exampleembodiments of the present disclosure.

Referring to FIG. 1B, there is shown an example of Beacon interval withSP with time division duplex (TDD) channel access.

In one embodiment, the mmWave distribution network use case defines thenew type of allocation which is slotted—service period with TDD channelaccess. An example of beacon interval with service period (SP) with TDDchannel access is shown in FIG. 1B. In this allocation, downlink anduplink transmissions are separated into different slots.

Referring to FIG. 1B, there is shown a beacon interval 152 that may becomprised of a beacon header interval (BHI) 154 and a data transmissioninterval (DTI) 156. The BHI 154 comprises a beacon time interval (BTI),an association beamforming training (A-BFT) interval, and anannouncement transmission interval (ATI). The DTI 156 may be comprisedof a contention based access period (CBAP 1) 158, a first service period(SP 1) 160, a second service period (SP 2) 162, and a second CBAP 2 163.The SP 2 162 may be an enhanced SP, in accordance with one or moreembodiments of the disclosure. Although this example shows that thereare four allocation periods (e.g., CBAP 1 158, SP 1 160, SP 2 162, andCBAP 2 163), the AP may allocate additional allocation periods asneeded. In addition, each of these allocation periods may be indicatedin the allocation control field of an extended schedule element.

In one or more embodiments, a new enhanced type of SP (e.g., SP 2 162)may be defined with time division data (TDD) access and may be dedicatedto mmWave distribution networks where the AP and STAs may performdownlink and uplink communications. For example, the SP 2 162 maycomprise one or more TDD intervals 164, where each of the one or moreTDD intervals 164 may be comprised of two groups of TDD slots (e.g., TDDslots 166 and TDD slots 168). The TDD slots 166 may be simplex transmit(TX) TDD slots and the TDD slots 168 may be simplex receive (RX) TDDslots. That is, the one or more of the TDD slots 166 may be used to senddownlink data from an AP/PCP to one or more STAs while the TDD slots 168may be used to send uplink data from one or more STAs to an AP/PCP. TheTDD slots 166 may include N TDD slots, where N is a positive integer.The TDD slots 168 may include M TDD slots, where M is a positiveinteger. In essence, the TDD slots 166 and the TDD slots 168 includeuplink and downlink TDD slots that may be used by the AP/PCP and/or oneor more STAs. Further, there may be a time gap between each pair of TDDslots (e.g., gaps 170, 172, and 174). These time gaps may be addedbetween the TDD slots as guard gaps to prevent interference between twoconsecutive TDD slots. These gaps may have equal time durations or mayvary based on the type of TDD slot. For example, the gap 172 between aTX TDD slot and an RX TDD slot may be the same as the gap 170 or may bedifferent. This may also be configurable by the network and/or by thesystem administrator. Further, at the beginning and end of the list ofTDD slots, there may be a gap 176 and a gap 178 respectively. Thesebeginning and end gaps may also be the same as the gaps between twoconsecutive TDD slots or may be different based on implementation.

The above requires an indication for STAs that the acknowledgment forthe frames transmitted to them should be sent in the scheduled slots.The Ack policy indications used in 802.11ad cannot solve this problem:the acknowledgment is required (Ack Policy=10 does not match), it shouldnot be sent immediately (Ack Policy=00 does not match), no BAR frameswill be transmitted (Ack Policy=11 does not match).

802.11 standard defines “Ack Policy subfield=01” as power savemulti-poll (PSMP) Ack. It is used in PSMP protocol which is not used in802.11ad.

In one embodiment, an enhanced acknowledgment policy system mayfacilitate the use of power save multi-poll (PSMP) protocol foracknowledgment. For example, Ack Policy subfield=01 may indicateScheduled BlockAck transmission. That means that STA which receivesquality of service (QoS) Data frame with Ack Policy subfield=01 willreturn a BlockAck frame during the scheduled time slot. The schedulingof this time slot may be done either implicitly by any pre-defined ruleor explicitly by sending the exact time period to STA in the additionalframe at the same PPDU.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 2 illustrates an acknowledgment and power save sequence 200,according to some example embodiments of the present disclosure.

Referring to FIG. 2, there is shown a PCP/AP 202 that is communicatingwith three STAs (e.g., user devices 224, 226, 228) in an MU MIMOcommunication.

The PCP/AP 202 may transmit an MU-PPDU packet which is addressed tothese STAs. After that, the PCP/AP 202 starts polling each STA foracknowledgment. For example, the PCP/AP 202 may send MU-MPDU 201 to thethree STAs (e.g., user devices 224, 226, 228). User device 224 mayreceive its portion of the MU-PPDU 201. The PCP/AP 202 may then requestfor acknowledgment by sending BAR 230 to the user device 224. The userdevice 224 may then, upon receiving the BAR 230, send a blockacknowledgment or an acknowledgment frame (e.g., BA/Ack 232). When thePCP/AP 202 receives the BA/ACK 232 from the user device 224, the PCP/AP202 may wait for a channel access period (e.g., a short inter-framespace (SIFS) time 203) to send a BAR 234 to the user device 228requesting an acknowledgment to the portion of the MU-PPDU 201 that isdestined for the user device 228. The user device 228 may then send aBA/ACK 236 in response to the BAR 234. The PCP/AP 202 may then send aBAR 238 to the user device 226 requesting acknowledgment to the portionof the MU-PPDU 201 that is destined for the user device 226. The userdevice 226 may then respond with a BA/ACK 240.

The PCP/AP 202 cannot send the MU-PPDU 201 and then let the user devicesacknowledge whenever they receive their portions of the MU-PPDU 201because of a high probability that the acknowledgments from these userdevices will cause interference and collisions on the PCP/AP's side.

A BAR/BA exchange as shown in FIG. 2 may cause large overhead increasinga duration of one MU cycle, and therefore may significantly reducethroughput.

In one or more embodiments, an acknowledgment and power save sequencemay limit an MU-MIMO acknowledgment flow to only one case in which allSTAs may be requested for a block acknowledgment after each MU PHYprotocol data unit (MU-PPDU).

In one or more embodiments, each STA calculates when it can go intopower save mode. For example, user device 224 may go to power save mode,it will calculate when it will receive a BAR 230 and goes into powersave mode until that time. The STA considers the shortest time toreceive the BAR 230, which in this case is SIFS. The user device 224already knows that it will be the first on the list based on informationexchanged with the PCP/AP 202 during the MU-MIMO group setup. The userdevice 228 knows that it's going to be the second in the list that hasto provide a block acknowledgment (e.g., BA/Ack 236) after it receivesthe BAR 234 from the PCP/AP 202. The user device 228 calculates the timethat it needs to wake up from its doze state (power save mode). Sincethe user device 228 knows that before it receives its BAR from thePCP/AP 202, there will be a BAR associated with the first device on thelist which is, in this case, the user device 224, a BA from the userdevice 224, following that there should be a BAR associated with theuser device 228. Considering that the minimal time frames are SIFS, theuser device 228 will be capable of determining when to wake up.

This procedure is not very accurate because there are inefficiencies inwhen a user device should wake up because this is based on the minimaltime that frames are expected to be sent and the user device testaccount a large enough time to ensure that it wakes up around the sametime it receives a BAR from the PCP/AP. There are additional assumptionsthat are used in this procedure. For example, the procedure assumes thatall user devices will transmit their acknowledgments.

The power save procedure may be based on an assumption that all STAstransmit a minimum BA, which may not be accurate in cases when BAs oflarger size are used.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 3 illustrates an acknowledgment and power save sequence 300, inaccordance with one or more example embodiments of the presentdisclosure.

Referring to FIG. 3, there is shown in PCP/AP 302 communicating withthree STAs (e.g., user device 324 (STA1), user device 326 (STA2), userdevice 328 (STA3)). The PCP/AP 302 may send a frame (e.g., MU-PPDU 301).The MU-PPDU 301 may be composed of a preamble, a header, and one or moreAggregated MAC protocol data unit (A-MPDU), where each A-MPDU is agrouping of MPDUs that are destined for a specific STA. For example,A-MPDU 301 a may be destined to STA1, A-MPDU 301 b may be destined toSTA2, and A-MPDU 301 c may be destined to STA3.

In one or more embodiments, BAR frames may be removed from anacknowledgment flow in order to reduce overhead. STAs may transmit theirBA during time slots scheduled by a personal basic service set controlpoint (PCP) AP (PCP/AP) for each STA. For example, the PCP/AP 302 maysend the MU-PPDU 301 without having to rely on sending BAR frames toinduce the STAs, belonging to the MU-MIMO group, to send theiracknowledgments. Instead, the PCP/AP 302 may facilitate sendinginformation associated with each STA's acknowledgment and relatedtiming.

In one or more embodiments, a PCP/AP (e.g., PCP/AP 302) may scheduletime slots for a BA transmission for each STA considering knowledgeabout the BA type for each STA and that BAs may be transmitted with thelowest modulation and coding scheme (MCS). A PCP/AP may inform each STAof the STA's respective BA Transmission Time (BATT) by includingscheduling information into the same MU PPDU. That is the PCP/AP 302 mayinclude scheduling information in the portion of the MU-PPDU that isintended for a specific STA (e.g., STA1, STA2, STA3). For example,A-MPDU 301 a may include scheduling information for STA1, A-MPDU 301 bmay include scheduling information for STA2, A-MPDU 301 c may includescheduling information for STA3.

In one or more embodiments, additional information may be included inthe MU-PPDU 301 to indicate to the STAs timing associated with a nextMU-PPDU (e.g., MU-PPDU 303) that may be sent by the PCP/AP 302. In theexample of FIG. 3, the MU-PPDU 301 may include information associatedwith time T1, T2, T3, and T4, where T1 is a time offset for STA1 to sendits acknowledgment (e.g., BA 331), T2 is a time offset for STA2 to sendits acknowledgment (e.g., BA 332), T3 is a time offset for STA3 to sendits acknowledgment (e.g., BA 333), and T4 is a time offset for thePCP/AP 302 to send a next MU-PPDU 303.

In one or more embodiments, each STA may implement a power save modeafter receiving an MU PPDU (e.g., an “end of frame” detection may beused for earlier receiver stop). The STA may wake up for BAtransmission, and may return to a power save mode again until the timedefined by AP (e.g., until the next MU PPDU transmission). The STA mayfollow the scheduling information and may wake up exactly for the STA'sBA transmission (e.g., BAs 331, 332, 333) and MU PPDU reception, therebyperforming power save in an effective and accurate way. For example,PCP/AP 302 may indicate to STA2 in A-MPDU 301 b an offset value thatindicates to the STA2 at which moment (e.g., T2) it should starttransmitting its block acknowledgment frame (e.g., BA 332). Similarly,the PCP/AP 302 may indicate to STA1 in A-MPDU 301 a an offset value thatindicates to the STA1 at which moment (e.g., T1) it should starttransmitting its block acknowledgment frame (e.g., BA 331). Further, thePCP/AP 302 may indicate to STA3 in A-MPDU 301 c an offset value thatindicates to the STA3 at which moment (e.g., T3) it should starttransmitting its block acknowledgment frame (e.g., BA 333). This way,the three STAs may be in doze state (low power state) from the time theSTAs received the MU-PPDU 301 (e.g., at time T0) until its respectiveoffset value. Then after the STA sends its BA frame, the STA can go backto a low power state until the next MU-PPDU (e.g., MU-PPDU 303) is sentat time T4.

In one or more embodiments, scheduling information delivered from an APto an STA may be specific to an STA, and may include a BATT Start offset(e.g., time offsets T1, T2, T3), which may indicate a beginning of timeslot provided by the PCP/AP 302 for an STA to transmit the STA's BA.

In one or more embodiments, scheduling information delivered from an APto an STA may be specific to an STA, and may include a next PPDU Startoffset (e.g., T4), which may indicate the moment when an STA shouldbegin listening to/for the PCP/AP 302. At this moment, the PCP/AP 302may either start transmitting the next MU PPDU in a current sequence ofan MU-MIMO transmission or may transmit a BAR to an STA if a solicitedBA was not received.

In one or more embodiments, to estimate the advantages of theacknowledgment and power save sequence 300 over existing techniques, acomparison may be conducted for both throughput and power save. Thefollowing assumptions were considered for the comparison. First, anamount of data (e.g., a PHY service data unit (PDSU)) for all STAs inMU-MIMO may be the same. Second, an AP may transmit each MU-MIMO streamusing MCS 12 (e.g., 4620 Mbps). Third, BAR and BA may be transmittedusing MCS 4 (e.g., 1155 Mbps). The results are shown in FIGS. 4A-4D.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIGS. 4A-4D illustrate throughput 400 of an acknowledgment and powersave sequence, in accordance with one or more example embodiments of thepresent disclosure.

In one or more embodiments, performance comparison results for the casewhen each STA transmit BA of minimal size (e.g., 25+8 bytes) aredemonstrated in FIGS. 4A and 4B. The graphs on FIGS. 4A and 4B maydemonstrate an equivalent throughput gain (e.g., acknowledgment overheadmay be taken into account) and power save gain (e.g., a reduction ofawake time for all STAs in MU-MIMO) of the enhanced procedure overlegacy procedures depending on the amount of data transmitted to eachSTA. Different curves of the graphs in FIGS. 4A and 4B may be related toa different number of STAs in MU-MIMO. The enhanced procedure mayprovide more than 100% gain for small and medium-size MU-MIMO framestransmission. Performance gains may be lower for cases in whichacknowledgment overhead is lower (e.g., a small number of STAs in the MUgroup, and big size of data frames).

In one or more embodiments, FIGS. 4C and 4D may demonstrate the samemetrics as FIGS. 4A and 4B, but each STA may transmit a BA of maximumsize (e.g., 25+256 bytes). The larger BA may reduce BAR frame overheadin existing techniques, and may thereby improve throughput, albeit at apotentially lower gain than shown in FIGS. 4A and 4B. The use of a largeBA may render existing power saves inaccurate and less effectivebecause, for example, an assumption that all STAs may transmit thesmallest possible BA. Therefore, FIGS. 4C and 4D may show improved powersave gains, as the enhanced acknowledgment and power save procedure mayreduce STA awake time by 75% in comparison with existing power saveprocedures.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 5 illustrates a multi-user data sequence 500, in accordance withone or more example embodiments of the present disclosure.

Referring to FIG. 5, there is a shown an AP 502 (e.g., also referred toherein “PCP/AP”) that may be communicating with three STAs (user devices524, 526, 528) in an MU-MIMO communication.

In one or more embodiments, a significant advantage of the enhancedacknowledgment and power save procedure may be that the enhancedprocedure is more flexible than existing techniques. For example, theenhanced acknowledgment and power save procedure may allow an AP toavoid having to request a BA from each STA after the STAs receive eachMU PPDU. The enhanced acknowledgment and power save procedure withMU-MIMO may allow the AP to elicit only one BA after each MU PPDUtransmission, thereby reducing acknowledgment overhead and increasingsystem throughput. For example, the AP 502 may send an EDMG MU PPDU 501to user device 524. The user device 524 may then respond with a BA/AC503, without having to require a BAR frame from the AP 502. Similarly,the user devices 526 and 528, would send their BA/ACKs (e.g., BA/ACKs507 and 511 respectively), after receiving the respective EDMG MU PPDUs(e.g., EDMG PPDUs 505 and 509 respectively) from the AP 502.

In one or more embodiments, an estimation of maximum possible APthroughput may provide a vivid demonstration of the improvements usingthe enhanced acknowledgment and power save procedure. To perform such anestimation, the following assumptions may be used. First, STAs may senda BA of minimal length (e.g., 25+8 bytes). Second, eight STAs may beused in MU-MIMO. Third, EDMG single channel (SC) MCS 20 (e.g., 8662.5Mbps) may be used for all STAs in MU-MIMO. Fourth, the channel bondingfactor may be four.

In one or more embodiments, Table 1 below may demonstrate the maximumpossible AP throughput for different amounts of transmitted data in alegacy (e.g., existing) flow, a proposed flow (e.g., the enhancedacknowledgment and power save procedure in which all eight STAs arerequested to send a BA), and another embodiment of the enhancedacknowledgment and power save procedure (e.g., a “proposed flow+” inwhich only one STA is requested to send a BA).

TABLE 1 Maximum Possible Throughput AP Throughput AP Throughput APThroughput PSDU, (Legacy flow), (Proposed flow), (Proposed flow+), bytesGbps Gbps Gbps 64 0.04 0.10 (+134%) 0.35 (+758%) 256 0.17 0.39 (+134%)1.41 (+755%) 1024 0.66 1.54 (+133%) 5.57 (+744%) 4096 2.62 6.06 (+131%)21.02 (+702%) 16384 10.20 22.74 (+123%) 68.49 (+572%) 65536 36.74 73.00(+99%) 157.34 (+328%)

As shown in Table 1, the proposed flow together with additionalacknowledgment overhead reduction may substantially increase the maximalpossible throughput provided by an 802.11ay AP.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIGS. 6A-6B illustrate the throughput of a multi-user data sequence, inaccordance with one or more example embodiments of the presentdisclosure.

In one or more embodiments, scheduling information may not betransmitted to STAs by an AP but may be known by STAs based on apredefined rule. For example, a responder (e.g., STA) may estimate astart time for BA transmission by considering a specified order. STAsmay transmit their BAs sequentially according to an order indicated in aheader of the MU-MIMO frame, or according to a list describing the MUgroup (e.g., a Group ID Set element). Other responders (e.g., STAs) maytransmit BAs of a fixed size using the lowest possible MCS. Estimating aBATT may include assuming that a first STA uses the longest BA type.

In one or more embodiments, FIGS. 6A and 6B may demonstrate thethroughput gains provided by such a flow. In most cases, the enhancedacknowledgment and power save procedure may result in better throughputthan existing legacy techniques. However, because of the assumption thatall STAs may transmit the longest possible BA, some degradation mayoccur (e.g., when STAs actually transmit the shortest BA).

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 7A depicts a flow diagram of an illustrative process 700 for usingenhanced acknowledgment and power save, in accordance with one or moreexample embodiments of the present disclosure.

At block 702, one or more processors of a device (e.g., user device 120of FIG. 1A) may determine a multi-user (MU) multiple-inputmultiple-output (MIMO) frame associated with a MU-MIMO group.

At block 704, the one or more processors of the device may determine afirst portion of the MU-MIMO frame associated with the first stationdevice of the MU-MIMO group, wherein the first portion comprises a firstindication of a first time offset associated with the first stationdevice.

At block 706, the one or more processors of the device may determine asecond portion of the MU-MIMO frame associated with the second stationdevice of the MU-MIMO group, wherein the second portion comprises asecond indication of a second time offset associated with the secondstation device.

At block 708, the one or more processors of the device may cause to sendthe MU-MIMO frame to the MU-MIMO group.

At block 710, the one or more processors of the device may identify afirst acknowledgment from the first station device based on the firsttime offset.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 7B depicts a flow diagram of an illustrative process 750 for usingenhanced acknowledgment and power save, in accordance with one or moreexample embodiments of the present disclosure.

At block 752, one or more processors of a device (e.g., AP 102 of FIG.1A) may identify a multi-user multiple-input multiple-output (MU-MIMO)frame received from a device, wherein the frame comprises one or moretime offsets.

At block 754, one or more processors of the device may transition from alower-powered mode to a higher-powered mode based on at least one of theone or more time offsets.

At block 756, one or more processors of the device may cause to send anacknowledgment frame to device.

At block 758, one or more processors of the device may transition fromthe higher-powered mode to the lower-powered mode after sending theacknowledgment frame.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 8 shows a functional diagram of an exemplary communication station800 in accordance with some embodiments. In one embodiment, FIG. 8illustrates a functional block diagram of a communication station thatmay be suitable for use as an AP 102 (FIG. 1A) or a user device 120(FIG. 1A) in accordance with some embodiments. The communication station800 may also be suitable for use as a handheld device, a mobile device,a cellular telephone, a smartphone, a tablet, a netbook, a wirelessterminal, a laptop computer, a wearable computer device, a femtocell, ahigh data rate (HDR) subscriber station, an access point, an accessterminal, or other personal communication system (PCS) device.

The communication station 800 may include communications circuitry 802and a transceiver 810 for transmitting and receiving signals to and fromother communication stations using one or more antennas 801. Thetransceiver 810 may be a device comprising both a transmitter and areceiver that are combined and share common circuitry (e.g.,communication circuitry 802). The communication circuitry 802 mayinclude amplifiers, filters, mixers, analog to digital and/or digital toanalog converters. The transceiver 810 may transmit and receive analogor digital signals. The transceiver 810 may allow reception of signalsduring transmission periods. This mode is known as full-duplex and mayrequire the transmitter and receiver to operate on different frequenciesto minimize interference between the transmitted signal and the receivedsignal. The transceiver 810 may operate in a half-duplex mode, where thetransceiver 810 may transmit or receive signals in one direction at atime.

The communications circuitry 802 may include circuitry that can operatethe physical layer (PHY) communications and/or media access control(MAC) communications for controlling access to the wireless medium,and/or any other communications layers for transmitting and receivingsignals. The communication station 800 may also include processingcircuitry 806 and memory 808 arranged to perform the operationsdescribed herein. In some embodiments, the communications circuitry 802and the processing circuitry 806 may be configured to perform operationsdetailed in FIGS. 2, 3, 4A, 4B, 4C, 4D, 5, 6A, 6B, 7A, and 7B.

In accordance with some embodiments, the communications circuitry 802may be arranged to contend for a wireless medium and configure frames orpackets for communicating over the wireless medium. The communicationscircuitry 802 may be arranged to transmit and receive signals. Thecommunications circuitry 802 may also include circuitry formodulation/demodulation, upconversion/downconversion, filtering,amplification, etc. In some embodiments, the processing circuitry 806 ofthe communication station 800 may include one or more processors. Inother embodiments, two or more antennas 801 may be coupled to thecommunications circuitry 802 arranged for sending and receiving signals.The memory 808 may store information for configuring the processingcircuitry 806 to perform operations for configuring and transmittingmessage frames and performing the various operations described herein.The memory 808 may include any type of memory, including non-transitorymemory, for storing information in a form readable by a machine (e.g., acomputer). For example, the memory 808 may include a computer-readablestorage device, read-only memory (ROM), random-access memory (RAM),magnetic disk storage media, optical storage media, flash memory devicesand other storage devices and media.

In some embodiments, the communication station 800 may be part of aportable wireless communication device, such as a personal digitalassistant (PDA), a laptop or portable computer with wirelesscommunication capability, a web tablet, a wireless telephone, asmartphone, a wireless headset, a pager, an instant messaging device, adigital camera, an access point, a television, a medical device (e.g., aheart rate monitor, a blood pressure monitor, etc.), a wearable computerdevice, or another device that may receive and/or transmit informationwirelessly.

In some embodiments, the communication station 800 may include one ormore antennas 801. The antennas 801 may include one or more directionalor omnidirectional antennas, including, for example, dipole antennas,monopole antennas, patch antennas, loop antennas, microstrip antennas,or other types of antennas suitable for transmission of RF signals. Insome embodiments, instead of two or more antennas, a single antenna withmultiple apertures may be used. In these embodiments, each aperture maybe considered a separate antenna. In some multiple-input multiple-output(MIMO) embodiments, the antennas may be effectively separated forspatial diversity and the different channel characteristics that mayresult between each of the antennas and the antennas of a transmittingstation.

In some embodiments, the communication station 800 may include one ormore of a keyboard, a display, a non-volatile memory port, multipleantennas, a graphics processor, an application processor, speakers, andother mobile device elements. The display may be an LCD screen includinga touchscreen.

Although the communication station 800 is illustrated as having severalseparate functional elements, two or more of the functional elements maybe combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may include one or more microprocessors, DSPs,field-programmable gate arrays (FPGAs), application specific integratedcircuits (ASIC s), radio-frequency integrated circuits (RFICs) andcombinations of various hardware and logic circuitry for performing atleast the functions described herein. In some embodiments, thefunctional elements of the communication station 800 may refer to one ormore processes operating on one or more processing elements.

Certain embodiments may be implemented in one or a combination ofhardware, firmware, and software. Other embodiments may also beimplemented as instructions stored on a computer-readable storagedevice, which may be read and executed by at least one processor toperform the operations described herein. A computer-readable storagedevice may include any non-transitory memory mechanism for storinginformation in a form readable by a machine (e.g., a computer). Forexample, a computer-readable storage device may include read-only memory(ROM), random-access memory (RAM), magnetic disk storage media, opticalstorage media, flash-memory devices, and other storage devices andmedia. In some embodiments, the communication station 800 may includeone or more processors and may be configured with instructions stored ona computer-readable storage device memory.

FIG. 9 illustrates a block diagram of an example of a machine 900 orsystem upon which any one or more of the techniques (e.g.,methodologies) discussed herein may be performed. In other embodiments,the machine 900 may operate as a standalone device or may be connected(e.g., networked) to other machines. In a networked deployment, themachine 900 may operate in the capacity of a server machine, a clientmachine, or both in server-client network environments. In an example,the machine 900 may act as a peer machine in peer-to-peer (P2P) (orother distributed) network environments. The machine 900 may be apersonal computer (PC), a tablet PC, a set-top box (STB), a personaldigital assistant (PDA), a mobile telephone, a wearable computer device,a web appliance, a network router, a switch or bridge, or any machinecapable of executing instructions (sequential or otherwise) that specifyactions to be taken by that machine, such as a base station. Further,while only a single machine is illustrated, the term “machine” shallalso be taken to include any collection of machines that individually orjointly execute a set (or multiple sets) of instructions to perform anyone or more of the methodologies discussed herein, such as cloudcomputing, software as a service (SaaS), or other computer clusterconfigurations.

Examples, as described herein, may include or may operate on logic or anumber of components, modules, or mechanisms. Modules are tangibleentities (e.g., hardware) capable of performing specified operationswhen operating. A module includes hardware. In an example, the hardwaremay be specifically configured to carry out a specific operation (e.g.,hardwired). In another example, the hardware may include configurableexecution units (e.g., transistors, circuits, etc.) and a computerreadable medium containing instructions where the instructions configurethe execution units to carry out a specific operation when in operation.The configuring may occur under the direction of the execution units ora loading mechanism. Accordingly, the execution units arecommunicatively coupled to the computer-readable medium when the deviceis operating. In this example, the execution units may be a member ofmore than one module. For example, under operation, the execution unitsmay be configured by a first set of instructions to implement a firstmodule at one point in time and reconfigured by a second set ofinstructions to implement a second module at a second point in time.

The machine (e.g., computer system) 900 may include a hardware processor902 (e.g., a central processing unit (CPU), a graphics processing unit(GPU), a hardware processor core, or any combination thereof), a mainmemory 904 and a static memory 906, some or all of which may communicatewith each other via an interlink (e.g., bus) 908. The machine 900 mayfurther include a power management device 932, a graphics display device910, an alphanumeric input device 912 (e.g., a keyboard), and a userinterface (UI) navigation device 914 (e.g., a mouse). In an example, thegraphics display device 910, alphanumeric input device 912, and UInavigation device 914 may be a touch screen display. The machine 900 mayadditionally include a storage device (i.e., drive unit) 916, a signalgeneration device 918 (e.g., a speaker), an enhanced acknowledgment andpower saving device 919, a network interface device/transceiver 920coupled to antenna(s) 930, and one or more sensors 928, such as a globalpositioning system (GPS) sensor, a compass, an accelerometer, or othersensor. The machine 900 may include an output controller 934, such as aserial (e.g., universal serial bus (USB), parallel, or other wired orwireless (e.g., infrared (IR), near field communication (NFC), etc.)connection to communicate with or control one or more peripheral devices(e.g., a printer, a card reader, etc.)).

The storage device 916 may include a machine readable medium 922 onwhich is stored one or more sets of data structures or instructions 924(e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 924 may alsoreside, completely or at least partially, within the main memory 904,within the static memory 906, or within the hardware processor 902during execution thereof by the machine 900. In an example, one or anycombination of the hardware processor 902, the main memory 904, thestatic memory 906, or the storage device 916 may constitutemachine-readable media.

The enhanced acknowledgment and power saving device 919 may beconfigured to perform the operations detailed in FIGS. 2, 3, 4A, 4B, 4C,4D, 5, 6A, 6B, 7A, and 7B.

It is understood that the above are only a subset of what the enhancedacknowledgment and power saving device 919 may be configured to performand that other functions included throughout this disclosure may also beperformed by the enhanced acknowledgment and power saving device 919.

While the machine-readable medium 922 is illustrated as a single medium,the term “machine-readable medium” may include a single medium ormultiple media (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 924.

Various embodiments may be implemented fully or partially in softwareand/or firmware. This software and/or firmware may take the form ofinstructions contained in or on a non-transitory computer-readablestorage medium. Those instructions may then be read and executed by oneor more processors to enable performance of the operations describedherein. The instructions may be in any suitable form, such as but notlimited to source code, compiled code, interpreted code, executablecode, static code, dynamic code, and the like. Such a computer-readablemedium may include any tangible non-transitory medium for storinginformation in a form readable by one or more computers, such as but notlimited to read only memory (ROM); random access memory (RAM); magneticdisk storage media; optical storage media; a flash memory, etc.

The term “machine-readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions for execution bythe machine 900 and that cause the machine 900 to perform any one ormore of the techniques of the present disclosure, or that is capable ofstoring, encoding, or carrying data structures used by or associatedwith such instructions. Non-limiting machine-readable medium examplesmay include solid-state memories and optical and magnetic media. In anexample, a massed machine-readable medium includes a machine-readablemedium with a plurality of particles having resting mass. Specificexamples of massed machine-readable media may include non-volatilememory, such as semiconductor memory devices (e.g., electricallyprogrammable read-only memory (EPROM), or electrically erasableprogrammable read-only memory (EEPROM)) and flash memory devices;magnetic disks, such as internal hard disks and removable disks;magneto-optical disks; and CD-ROM and DVD-ROM disks.

The instructions 924 may further be transmitted or received over acommunications network 926 using a transmission medium via the networkinterface device/transceiver 920 utilizing any one of a number oftransfer protocols (e.g., frame relay, internet protocol (IP),transmission control protocol (TCP), user datagram protocol (UDP),hypertext transfer protocol (HTTP), etc.). Example communicationsnetworks may include a local area network (LAN), a wide area network(WAN), a packet data network (e.g., the Internet), mobile telephonenetworks (e.g., cellular networks), plain old telephone (POTS) networks,wireless data networks (e.g., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16family of standards known as WiMax®), IEEE 802.15.4 family of standards,and peer-to-peer (P2P) networks, among others. In an example, thenetwork interface device/transceiver 920 may include one or morephysical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or moreantennas to connect to the communications network 926. In an example,the network interface device/transceiver 920 may include a plurality ofantennas to wirelessly communicate using at least one of single-inputmultiple-output (SIMO), multiple-input multiple-output (MIMO), ormultiple-input single-output (MISO) techniques. The term “transmissionmedium” shall be taken to include any intangible medium that is capableof storing, encoding, or carrying instructions for execution by themachine 900 and includes digital or analog communications signals orother intangible media to facilitate communication of such software. Theoperations and processes described and shown above may be carried out orperformed in any suitable order as desired in various implementations.Additionally, in certain implementations, at least a portion of theoperations may be carried out in parallel. Furthermore, in certainimplementations, less than or more than the operations described may beperformed.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments. The terms “computing device,” “userdevice,” “communication station,” “station,” “handheld device,” “mobiledevice,” “wireless device” and “user equipment” (UE) as used hereinrefers to a wireless communication device such as a cellular telephone,a smartphone, a tablet, a netbook, a wireless terminal, a laptopcomputer, a femtocell, a high data rate (HDR) subscriber station, anaccess point, a printer, a point of sale device, an access terminal, orother personal communication system (PCS) device. The device may beeither mobile or stationary.

As used within this document, the term “communicate” is intended toinclude transmitting, or receiving, or both transmitting and receiving.This may be particularly useful in claims when describing theorganization of data that is being transmitted by one device andreceived by another, but only the functionality of one of those devicesis required to infringe the claim. Similarly, the bidirectional exchangeof data between two devices (both devices transmit and receive duringthe exchange) may be described as “communicating,” when only thefunctionality of one of those devices is being claimed. The term“communicating” as used herein with respect to a wireless communicationsignal includes transmitting the wireless communication signal and/orreceiving the wireless communication signal. For example, a wirelesscommunication unit, which is capable of communicating a wirelesscommunication signal, may include a wireless transmitter to transmit thewireless communication signal to at least one other wirelesscommunication unit, and/or a wireless communication receiver to receivethe wireless communication signal from at least one other wirelesscommunication unit.

As used herein, unless otherwise specified, the use of the ordinaladjectives “first,” “second,” “third,” etc., to describe a commonobject, merely indicates that different instances of like objects arebeing referred to and are not intended to imply that the objects sodescribed must be in a given sequence, either temporally, spatially, inranking, or in any other manner.

The term “access point” (AP) as used herein may be a fixed station. Anaccess point may also be referred to as an access node, a base station,an evolved node B (eNodeB), or some other similar terminology known inthe art. An access terminal may also be called a mobile station, userequipment (UE), a wireless communication device, or some other similarterminology known in the art. Embodiments disclosed herein generallypertain to wireless networks. Some embodiments may relate to wirelessnetworks that operate in accordance with one of the IEEE 802.11standards.

Some embodiments may be used in conjunction with various devices andsystems, for example, a personal computer (PC), a desktop computer, amobile computer, a laptop computer, a notebook computer, a tabletcomputer, a server computer, a handheld computer, a handheld device, apersonal digital assistant (PDA) device, a handheld PDA device, anon-board device, an off-board device, a hybrid device, a vehiculardevice, a non-vehicular device, a mobile or portable device, a consumerdevice, a non-mobile or non-portable device, a wireless communicationstation, a wireless communication device, a wireless access point (AP),a wired or wireless router, a wired or wireless modem, a video device,an audio device, an audio-video (A/V) device, a wired or wirelessnetwork, a wireless area network, a wireless video area network (WVAN),a local area network (LAN), a wireless LAN (WLAN), a personal areanetwork (PAN), a wireless PAN (WPAN), and the like.

Some embodiments may be used in conjunction with one way and/or two-wayradio communication systems, cellular radio-telephone communicationsystems, a mobile phone, a cellular telephone, a wireless telephone, apersonal communication system (PCS) device, a PDA device whichincorporates a wireless communication device, a mobile or portableglobal positioning system (GPS) device, a device which incorporates aGPS receiver or transceiver or chip, a device which incorporates an RFIDelement or chip, a multiple input multiple output (MIMO) transceiver ordevice, a single input multiple output (SIMO) transceiver or device, amultiple input single output (MISO) transceiver or device, a singleinput single output (SISO) transceiver or device, a device having one ormore internal antennas and/or external antennas, digital video broadcast(DVB) devices or systems, multi-standard radio devices or systems, awired or wireless handheld device, e.g., a smartphone, a wirelessapplication protocol (WAP) device, or the like.

Some embodiments may be used in conjunction with one or more types ofwireless communication signals and/or systems following one or morewireless communication protocols, for example, radio frequency (RF),infrared (IR), frequency-division multiplexing (FDM), orthogonal FDM(OFDM), time-division multiplexing (TDM), time-division multiple access(TDMA), extended TDMA (E-TDMA), general packet radio service (GPRS),extended GPRS, code-division multiple access (CDMA), wideband CDMA(WCDMA), CDMA 2000, single-carrier CDMA, multi-carrier CDMA,multi-carrier modulation (MDM), discrete multi-tone (DMT), Bluetooth□,global positioning system (GPS), Wi-Fi, Wi-Max, ZigBee, ultra-wideband(UWB), global system for mobile communications (GSM), 2G, 2.5G, 3G,3.5G, 4G, fifth generation (5G) mobile networks, 3GPP, long termevolution (LTE), LTE advanced, enhanced data rates for GSM Evolution(EDGE), or the like. Other embodiments may be used in various otherdevices, systems, and/or networks.

Certain aspects of the disclosure are described above with reference toblock and flow diagrams of systems, methods, apparatuses, and/orcomputer program products according to various implementations. It willbe understood that one or more blocks of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and the flowdiagrams, respectively, may be implemented by computer-executableprogram instructions. Likewise, some blocks of the block diagrams andflow diagrams may not necessarily need to be performed in the orderpresented, or may not necessarily need to be performed at all, accordingto some implementations.

These computer-executable program instructions may be loaded onto aspecial-purpose computer or other particular machine, a processor, orother programmable data processing apparatus to produce a particularmachine, such that the instructions that execute on the computer,processor, or other programmable data processing apparatus create meansfor implementing one or more functions specified in the flow diagramblock or blocks. These computer program instructions may also be storedin a computer-readable storage media or memory that may direct acomputer or other programmable data processing apparatus to function ina particular manner, such that the instructions stored in thecomputer-readable storage media produce an article of manufactureincluding instruction means that implement one or more functionsspecified in the flow diagram block or blocks. As an example, certainimplementations may provide for a computer program product, comprising acomputer-readable storage medium having a computer-readable program codeor program instructions implemented therein, said computer-readableprogram code adapted to be executed to implement one or more functionsspecified in the flow diagram block or blocks. The computer programinstructions may also be loaded onto a computer or other programmabledata processing apparatus to cause a series of operational elements orsteps to be performed on the computer or other programmable apparatus toproduce a computer-implemented process such that the instructions thatexecute on the computer or other programmable apparatus provide elementsor steps for implementing the functions specified in the flow diagramblock or blocks.

Accordingly, blocks of the block diagrams and flow diagrams supportcombinations of means for performing the specified functions,combinations of elements or steps for performing the specified functionsand program instruction means for performing the specified functions. Itwill also be understood that each block of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and flowdiagrams, may be implemented by special-purpose, hardware-based computersystems that perform the specified functions, elements or steps, orcombinations of special-purpose hardware and computer instructions.

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainimplementations could include, while other implementations do notinclude, certain features, elements, and/or operations. Thus, suchconditional language is not generally intended to imply that features,elements, and/or operations are in any way required for one or moreimplementations or that one or more implementations necessarily includelogic for deciding, with or without user input or prompting, whetherthese features, elements, and/or operations are included or are to beperformed in any particular implementation.

Many modifications and other implementations of the disclosure set forthherein will be apparent having the benefit of the teachings presented inthe foregoing descriptions and the associated drawings. Therefore, it isto be understood that the disclosure is not to be limited to thespecific implementations disclosed and that modifications and otherimplementations are intended to be included within the scope of theappended claims. Although specific terms are employed herein, they areused in a generic and descriptive sense only and not for purposes oflimitation.

What is claimed is:
 1. A device, the device comprising processingcircuitry coupled to storage, the processing circuitry configured to:determine a multi-user (MU) multiple-input multiple-output (MIMO) frameassociated with a MU-MIMO group; determine a first indication includedin the MU-MIMO frame, wherein the first indication is associated with afirst station device of the MU-MIMO group, and wherein the firstindication indicates a first time slot assigned to the first station;determine a second indication included in the MU-MIMO frame, wherein thesecond indication is associated with a second station device of theMU-MIMO group, and wherein the second indication indicates a second timeslot assigned to the second station, wherein the first indication isdifferent from the second indication, and wherein the first time slot isdifferent from the second time slot, and wherein the first stationdevice is different from the second station device; cause to send theMU-MIMO frame to the MU-MIMO group; identify a first acknowledgment fromthe first station device based on the first time slot; and identify asecond acknowledgement from the second station device based on thesecond time slot.
 2. The device of claim 1, wherein the first time slotis assigned to the first station to send an acknowledgment afterreceiving the MU-MIMO frame.
 3. The device of claim 1, wherein the firstacknowledgment acknowledges that the first station device received theMU-MIMO frame.
 4. The device of claim 1, wherein a portion of theMU-MIMO frame comprises a third time slot associated with a time to senda second MU-MIMO frame.
 5. The device of claim 1, wherein the first timeslot indicates to the first station device to enter an active mode afterbeing in a doze state.
 6. The device of claim 1, wherein the firstacknowledgment is associated with a minimum modulation and codingscheme.
 7. The device of claim 1, wherein the second acknowledgmentacknowledges that the second station device received the MU-MIMO frame.8. The device of claim 1, further comprising a transceiver configured totransmit and receive wireless signals.
 9. The device of claim 8, furthercomprising an antenna coupled to the transceiver to cause to send theMU-MIMO frame.
 10. A non-transitory computer-readable medium storingcomputer-executable instructions which when executed by one or moreprocessors result in performing operations comprising: determining amulti-user (MU) multiple-input multiple-output (MIMO) frame associatedwith a MU-MIMO group; determining a first indication included in theMU-MIMO frame, wherein the first indication is associated with a firststation device of the MU-MIMO group, and wherein the first indicationindicates a first time slot assigned to the first station; determining asecond indication included in the MU-MIMO frame, wherein the secondindication is associated with a second station device of the MU-MIMOgroup, and wherein the second indication indicates a second time slotassigned to the second station, wherein the first indication isdifferent from the second indication, and wherein the first time slot isdifferent from the second time slot, and wherein the first stationdevice is different from the second station device; causing to send theMU-MIMO frame to the MU-MIMO group; identifying a first acknowledgmentfrom the first station device based on the first time slot; andidentifying a second acknowledgement from the second station devicebased on the second time slot.
 11. The non-transitory computer-readablemedium of claim 10, wherein the first time slot is assigned to the firststation to send an acknowledgment after receiving the MU-MIMO frame. 12.The non-transitory computer-readable medium of claim 10, wherein thefirst acknowledgment acknowledges that the first station device receivedthe MU-MIMO frame.
 13. The non-transitory computer-readable medium ofclaim 10, wherein a portion of the MU-MIMO frame comprises a third timeslot associated with a time to send a second MU-MIMO frame.
 14. Thenon-transitory computer-readable medium of claim 10, wherein the firsttime slot indicates to the first station device to enter an active modeafter being in a doze state.
 15. The non-transitory computer-readablemedium of claim 10, wherein the first acknowledgment is associated witha minimum modulation and coding scheme.
 16. The non-transitorycomputer-readable medium of claim 10, wherein the second acknowledgmentacknowledges that the second station device received the MU-MIMO frame.17. A method comprising: determining, by one or more processors, amulti-user (MU) multiple-input multiple-output (MIMO) frame associatedwith a MU-MIMO group; determining a first indication included in theMU-MIMO frame, wherein the first indication is associated with a firststation device of the MU-MIMO group, and wherein the first indicationindicates a first time slot assigned to the first station; determining asecond indication included in the MU-MIMO frame, wherein the secondindication is associated with a second station device of the MU-MIMOgroup, and wherein the second indication indicates a second time slotassigned to the second station, wherein the first indication isdifferent from the second indication, and wherein the first time slot isdifferent from the second time slot, and wherein the first stationdevice is different from the second station device; causing to send theMU-MIMO frame to the MU-MIMO group; identifying a first acknowledgmentfrom the first station device based on the first time slot; andidentifying a second acknowledgement from the second station devicebased on the second time slot.
 18. The method of claim 17, wherein thefirst time slot is assigned to the first station to send anacknowledgment after receiving the MU-MIMO frame.
 19. The method ofclaim 17, wherein the first acknowledgment acknowledges that the firststation device received the MU-MIMO frame.
 20. The method of claim 17,wherein a portion of the MU-MIMO frame comprises a third time slotassociated with a time to send a second MU-MIMO frame.